Iraq is losing the educated elite of doctors, lawyers, academics and businessmen who are vital to securing a stable future. There is also fear that their departure will leave a vacuum to be filled by religious extremists.

Outside the shelter of the Green Zone, home to the American and Iraqi political leadership, lawlessness has overtaken the capital.

Prof Abdul Sattar Jawad, the head of English literature at Baghdad University, will leave next month to take up a post in Jordan. Two of his colleagues left recently after being intimidated.

At his home in east Baghdad the professor answered the door with an outstretched hand. In the other hand he carried a loaded revolver "because I don't trust anybody nowadays".

While the lack of basic needs and a barely functioning infrastructure are considerable hardships, it is the daily threat of death that was the catalyst for his decision. Since the new government came to power in April there have been up to 3,000 civilian deaths, about half attributed to criminal activity.

"I love my country but I am unable to do any service for the people because it is overrun by fanatics and extremists," Prof Jawad said. "The streets are ruled by gangs, looters and goons."

Last month he resigned a position as dean of arts after "religious animals" surrounded his office and shouted "war-like slogans".

The threats have also forced him to close down two English newspapers he ran because "it now is anti-religious to have free speech, liberal minds and civilisation in this country".

Prof Jawad's wife Sarah, a former geography teacher, said she now wore a headscarf to avoid being harassed by religious extremists.

For his son Omar Jawad, a single 30-year-old lawyer working for a British company in the Green Zone, the one ambition is to leave Iraq "as quickly as possible, as soon as I find somewhere to go".

He added: "I see a lot of educated people leaving Iraq. I talked this morning to one of my friends who has a PhD in law. He has just resigned from his job and is going. You hear so many similar stories. It is more security problems than economic. Under sanctions [imposed on Saddam Hussein by the United Nations after the Gulf war] we had no problems like this."

Aside from the daily risk of kidnap, suicide bombers and drive-by shootings, his half hour journey into work is now a two-hour slog through roadblocks.

There are no land-line telephones, water has to be pumped from a well and electricity is on for only two hours a day compared with 21 under Saddam. In a country that perches on a lake of oil, the petrol queues last up to four hours.

"I am not very optimistic," Mr Jawad said. "We have this fear of civil war because when the Americans are out it will be left to the Iraqis.

"It is two years now since the war ended and we see no development."

For the past three years Mahir Mahmood, 37, has built a successful business importing cars and spares but by the autumn he will be gone because he fears his wife and four children will be held to ransom by criminals.

"I think the bombs, explosions and killings are enough for anyone to leave the country," he said. " What good has the government done for the people to make them stay?"

He has arranged an apartment for his family in Syria where he knows of half a dozen other Iraqi businessman who have already moved.

Baghdad's doctors suffer most of all. They are now authorised to carry firearms after some were killed by angry relatives of dead patients and after threats by police officers demanding immediate treatment for injured colleagues.

Dr Tariq Bahjat, who became a hospital director in Baghdad after his predecessor was killed and where a radiologist was recently shot dead, said: "No one can provide doctors with protection. I am afraid the same will happen to me; that is why I will go abroad."

A spokesman for the prime minister, Ibrahim al-Jaafari, said: "It is a worry, of course, and they are going to be difficult to replace.

"Many people are getting jobs abroad and in terms of what the government can do about it? Very little."